For some questions on this, like how they got 3D printers and filament in Iran? That's simple. China is the largest consumer of Iran's oil. In the China-Iran deal in 2021, on a 25-year deal, it was about supporting the transformation of Iran's economy into something else. China's investment was barely 27 billion over the last 15 years, and in exchange for their oil, they mostly got cheap Chinese consumer goods flooding their markets and harming their locally made products (sounds familiar yet?), including 3D printers, filament, and other parts.